I want to know if the Betty pubic dyes works on hair resistant to dyes?
Thanks

If the hair you are dyeing is resistant to dyes (I'm assuming you're talking about extensions of some sort) then Betty hair dye most like will not work. If you mean that your is difficult to dye because it's very dark then Betty will work as well as any other retail product. We can only suggest you do a patch test and wait 24 hours to see the results.